Tower structure



Jan. 18, 1949. R JOHN 2,459,198

TOWER STRUCTURE Filed Aug. 9, 1945 2 Sheets-Sheet 1 mma A TT'OR/VIY Jan. 18, 1949. E, R, ST, JOHN 2,459,198

TOWER STRUCTURE Filed Aug. 9, 1945 2 Sheets-Sheet 2 Brass 52 2 [II I i 5/ 2? 22 2 2; 4.9 i E 23 I l I 50 F 57- 5 l I v 1 ,My

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- flash/s A 57? John ATTORNEY Patented Jan. 18, 1949 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 2 Claims.

This invention relates to a tower structure and method of assembly and disassembly; particularly the invention relates to a radio antenna.

An object of this invention is to provide a tower structure such as a radio antenna that is capable of being assembled in a horizontal position close to the ground and then raised to a vertical position without the necessity of having men do any high climbing.

Another object is to provide a tower structure such as a, radio antenna which can be dismantled into relatively short sections for convenient transportation.

Another object is to provide a simple and convenient method for erecting a tower.

Another object is to provide a tower structure such as a radio antenna. that can be assembled and erected by relatively unskilled personnel.

Another object is to provide a tower structure such as a radio antenna that is suitable for tropical duty.

Further objects and advantages of this invention as well as its construction arrangement and operation, will be apparent from the following description and claims in connection with the accompanyin drawings in which:

Fig. l is a front elevation of the radio antenna assembly in its erected position;

Fig. 2 is a plan view of the ground frame used with the assembly of Fig. 1.

Fig. 3 is an enlarged perspective view of a portion of the antenna assembly of Fig. 1;

Fig. 4 is a sectional View of one of the mast tops of the antenna assembly shown in Fig. 1;

Fig. 5 is a sectional view of the mast top taken on the line 5--5 in Fig. 4;

Fig. 6 is an enlarged view of one of the joints shown in Fig. 3;

Fig. '7 is a view of the base lock of the antenna assembly of Fig. 1; and

Figs. 8, 9, 10, 11 and 12 are schematic illustrations of progressive steps in the erection of the radio antenna assembly of Fig. 1.

Fig. 1 shows a tower generally designated as II comprising a vertical center member l2 integrally braced by cross struts I3 and tension rods H3. These members are shown in greater detail in Fig. 3. The tower II is rotatably supported as at I! upon a trunnion 18 through approximately its lower midsection. The supporting trunnion I3 is engaged and supported by bearings l9 upon the tops of two masts 29 in turn rotatably secured to pedestals 2| upon a ground frame 22. This arrangement allows the tower I I and masts 20 to swing or rotate in parno u allel vertical planes as will be described in detail below.

The base of the tower II is secured by a lock 23 connected to the ground frame 22. The masts 26 are provided with stays 24 which are also connected to the ground frame 22 and arranged such that in combination with the trunnion I8 and ground frame Z-Zthey form a system of bracing for maintaining the masts 2B in a vertical position. These stays 24 can be comprised of sections of rod of convenient length shackled together as at 25 and. provided with turnbuckles 26 so that they can be placed under a suitable tension. The ground frame 22 is provided with suitable earth anchorages 21 to resist upward forces caused by the wind and by the tackle used in erecting the tower.

Fig. 2 shows the arrangement of the ground frame 22. This is preferably buried below the surface of the ground. Suitable connections for the stays 24 are provided at the positions 28. The pedestals 2! are secured at 29 and the lock 23 for the tower base is secured at 3B. The necessary connections for attaching snatch blocks and other sheaves and winches required for tilting the tower II and masts 20 from horizontal to vertical position (described below) are also connected to the ground frame 22.

Fig. 3 shows a typical portion of the tower N. All members are made of an aluminum alloy or other light durable material of suitable strength.

The center member I2 is made up of sections of tubular material of convenient length joined together as at 3!. The tube sections can be of progressively decreasing diameter on each side of the supporting trunion I8. The joints are tapered and keyed or otherwise secured and are machined for accurate fitting. Around the joints are collars 32 that can comprise half sections bolted together at 32a as shown in Fig. 6. These v collars 32 are provided with connections as at 33 for the cross struts I3 and with lugs as at 3 3 having holes for receiving shackles 35 of the tension rods I6.

The cross struts l3 are also made of tubing. The end of each cross strut I3 is provided with suitable connections 35 having lugs provided with holes for receiving shackles 35 of the tension rods I 6 (see Fig. 5). The vertical tension rods can be comprised of sections shackled together as at 3] so as to be of lengths of convenience in handling. The sizes of the cross struts i3 and tension rods it can also progressively decrease on each side of the trunnion I8.

Optionally other tower designs may be used 3 with the trunnion and mast arrangement without departing from the principles of the invention as described and claimed herein.

The trunnion I8 and bearing I9 on one of the I mast topsare shown in detail in Figs. 4 and 5.

The bearing I9 consists of a split block having a base section 38. residing on a topplate..39 oi the mast 2U. Acap section 40 fits overrthe trunnion I8 and is secured to the base section 38- by bolts 4| (Fig. 4) which also hold the base section38G extension Mi providedwith a washer 35 and nut 16..

Figs 4 and 5 also. show the manner in. which the stays-.2 3 are secured to the mast top. Lugs Ii'I having holes 48. for rooeiving'the; shackles 2.5.. ofthe stays 24 are bolted or otherwisesecured to the'masttop below the bearing I9: Fig. 5 further shows connecting members. 36 for receiving the shackles 35 of the tension rods I6.

Fig. 7 shows the ground'lock23 in detail. This lock 23. comprises a two piece cast block 49'bo1ted or. otherwise secured to the ground frame 22. as at 50. The tower base is provided with a rubber insulated gudgeon pin 5 I. that fits in the block 4.9and in the base oflthe center member I2.

Fig. 7 also shows a base collar 52 having lugs 52a for receiving the tension rods. It; This base collar 52 .isfurther provided with a bail 53 for connecting tackle. as-at. 54"for erecting the towerv In assembling. and erecting the antenna the groundis first suitably graded, .trenches and holes.

for. the. ground frame 22 and anchorage 21. excavated; the groundframe. 22. and anchorages 21' are assembled in place. and the trenches and anchorages filled and thoroughly tamped. The pedestals 21! forv the. masts 20, the ground lock.2,3 and connections. for stays 24 and for sheaves, snatchblocks and winches arethen connected to the ground frame 22. The two masts. 20. are assembled in ahori'zontal position together. with the trunnion I8 of. the tower H and are attached to the. pedestals 2.I Thestays 214 are attached to themast. tops. By gin poles, mobile cranes or other convenient means the mastends are raised to. substantially the positionshown in Fig. 8-and supported by any suitable. means as at. 55.

The tower II. is next. assembled from. itscomponent. sections starting from. the trunnion I8 and. workingtoward. both. ends. Tower It is supportedat intervals by suitable. means as. at 56 (Fig, 9).. to enable-the. bracing andstruts toclear the-ground. Whenthetower II isccmpletely as.- sembled with all rods and joints tightened- ("asin FigQ). a dolly 51. is placed under. thetopend. The bails 5.3..areattached to. thetower baseandtackle. lines. 55' and. 5.9 aresecured thereto. All supports are. now removed.v and. thetower II. rests on the. dolly 51 andtrunnion I8..

The tower. base and mast tops are next. pulled upward. and in the. direction of.v the tower base by mobile crances,. gin. poles or other convenient meansto av reasonable height such as that shown in Fig. 10.. At. this position thedolly. 51 is. pulled forward by meansv of. a. winch. 6.0. and. tackle- 6 I until the masts are in a. vertical'position as The trunnion.

shown in Fig. 11. Stays 24 are then connected to the ground frame and properly tightened.

The tower II is now raised by swinging it through a vertical plane about the axis of the trunnion l8 by means of tackle lines 58 and 59 and winches B2 and 63 as shown in Fig. 11. The baseotthe tower II swingsinto a-halfsection of the groundlock 23 and? is secured: by'bolting the other half section in place. Fig. 12 shows the tower II in the final position with all. stays properly tightened and braced.

If the tower is to be erected by experienced erectors, automatic torque wrenches can be used to. control the initial tension in all the rods and stays. If, however; the toweris to be assembled and erected by unskilled personnel, all parts are actually fabricated and machined, all threading of rods, devices, turnbuckles, sleeve nuts and all taper keyed joints between pipe sections are made so accurately that, when every screwed joint is tightened up until shouldered; contact surfaces are in contact. By this 'means predetermined initial stresses are produced by unskilled workers,

By thus applying the proper initial stresses the deflections are reduced as much as 50-per centin some antenna designs and dangerous whipping eliminated.

All parts of the proposed radio antenna can be ticularly well adapted for erection andusein the tropics where. ice and sleet are notv encountered;

It. is to be understood that vari'ouschanges may be made in this invention without departing from the, spirit. and scope thereof as set. forth in the appended claims. v

The invention described herein may be manufactored. and used. by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is: e

l. A port-abletower structure. assembled from, a plurality of relatively small individual units and adapted to. be erected. and taken downv by personnel. confined. to the ground; said tower structure comprising a ground frame embedded in.

the ground, said frame having. a plurality of anchors exposed at the. surface. of the ground. a pair of elongated and rigid. supports. disposed in parallel spaced relation, said supports each. having. one end swingably attached to an anchor so that said supports can swing in. parallelpaths, a transverse trunnion rigidly interconnecting the ends of said supports,.stays between said anchors.

and the ends of said supports adjacentsaid trumnion. for. securing said supports in. vertical position with said, trunnion extending, horizontally,

an. elongated andv integrally braced. single tube tower formed from. a plurality of. individual sec.- tions, saidtower. being rotatably mounted upon said trunnion and adapted to be disposed vertical position with one and depending from the. trunnion into proximity with the ground, and a: lock on said ground frame for engaging said de-; pending tower end to lockthe tower in vertical position.

2. Atower structure.comprisingaground; frame embedded in the ground, said frame. having a plurality of anchors exposed at the surface of the REFERENCES CITED ground, a pair of elongated and rigid supports disposed in parallel spaced relation, said supports g i ggfizg gg are of record in the each having one end swingably attached to an anchor so that said supports can swing in par- 5 v ITED STATES PATENTS allel paths, a transverse trunnion rigidly inter- Number Name Date connecting the ends of said supports, stays be- 717,916 Perry Jan 6 1903 tween said anchors and the ends of said sup- P984230 Miller et a1 Feb. 14 1911 ports adjacent said trunnion for securing said 1,897 373 Gertm et a1 Feb 1933 supports in vertical position with said trunnion 10 L extending horizontally, a tower rotatably mounted FOREIGN PATENTS f upon said trunnion and'adapted to be disposed Number Country Date in vertical position with one end depending from 65.413 Switzerland June 21 1913 the trunnion into proximity with the ground, and a lock on said ground frame for engaging 15 said depending tower end to lock the tower in vertical position.

ERASTUS R. ST. JOHN. 

